Chase lockup bar assembly



1966 D. P. WESTRA CHASE LOCKUP BAR ASSEMBLY Filed NOV. 4, 1964 fia. 4.

INVENTOR. fl/W M65724 ATTORNEYS United States Patent 3,288,062 CHASE LOCKUP BAR ASSEMBLY Dan P. Westra, Grand Haven, Mich., assignor to The Challenge Machinery Company, Grand Haven, Mrch., a corporation of Michigan Filed Nov. 4, 1964, Ser. No. 408,874 15 Claims. (Cl. 101-390) This invention relates to lockup bar assemblies such as are used in the locking of printing forms into position upon the bed of a printing press, and more particularly to such a lockup bar assembly which by the actuation of a single manual control locks itself into position upon the press bed and also exerts a constant retaining force against the printing form.

Lockup bar assemblies have for many years been used in the printing arts in order to lock the type-filled galleys into place upon the bed of the press, so that the printing press rollers could be drawn across the type faces and printing could be accomplished. The prime requisite of such an assembly is that it secures the galley or chase into the bed of the press in such a manner that the type cannot be moved during the printing process, since this results in a blurring of the printing ink and produces illegibly printed words.

Early lockup bar assemblies were designed only to exert a powerful force between the side rails of the press bed, in order to prevent the lockup bar and printing form from actually shifting under the stresses of printing. It has long been known, however, that such a device was not satisfactory, since even though it did prevent actual shifting of the printing form, it nonetheless exerted no continuous force against the form. Instead, it merely res-ted snugly against the form and permitted minor movements of the form and type during the printing operation which at times were sufiicient t-o unacceptably blur the printing.

In recognition of this situation, several previous devices sought to incorporate means for applying some kind of pressure against the printing form. Most such devices utilized various types of spring-loaded members for contacting the form. These devices were secured into place upon the bed of the press by first pressing the lockup bar against the printing form until the spring member was partially or fully loaded, and in this position actuating the means which locked the bar across the bed, thereby maintaining the printing form under some degree of continuous spring tension. In such an arrangement, however, the force exerted against the form is necessarily less than that which the operator alone can exert. Moreover, it is a yielding pressure which may be varied by the stresses which occur during printing. It is therefore difiicult or impossible to obtain uniform and reliable operation with such -a device.

Another type of previous device is that disclosed in US. Patent No. 2,823,608 issued to D. D. Vandercook et al. This device utilizes a manually operable cam-type of force exerting mechanism found in earlier devices, but instead of using this mechanism for merely exerting force against the sides of the printing press bed, it adds a second cam follower and a force bar such that the cam mechanism is enabled to exert force simultaneously against the sides of the bed and also against the printing form. In this manner, the form is under a constant and fixed mechanical force which tends to rigidly fix it in place upon the bed.

The present invention provides a new and unique arrangement of a lockup bar assembly which from one point of view integrates into a single mechanism all of the best features of previous lockup bar assemblies, thereby eliminating the limitations which each possessed alone. From another point of view, however, the present inventive lockup bar assembly presents a totally new concept of struc- Patented Nov. 29, 1966 ture and operation for such a device, and it is a major objective of this invention to provide a lockup bar assembly which by means of such a new structural concept provides a device having a single manually operable actuating member by which the device is caused to first lock itself rigidly into position upon the press bed and then to exert a continuous and very strong, but not inflexible, force against the printing form, tending to maintain it firmly in place upon the bed.

Another object of the invention is to insure that the lockup bar always locks itself securely into position before exerting any force against the printing form, and to insure that the lockup bar always exerts a stronger force for holding itself in position that it does for holding the printing form within the bed. 'In this manner, the lockup bar can never exert such a force against the printing form that it will cause itself to move relative to the bed of the press, since the actuating member is uniquely arranged to always exert the first and foremost force against the sides of the press bed.

Yet another object of the present invention is to provide a locking bar assembly which increases the force exerted against the sides of the press bed with increases in the force applied to the printing form.

Still another object of the present invention is to provide a lockup bar assembly which accomplishes the abovedescribed operation through the elastic deformation of a pressure bar, and which provides the above-described force differential by the bending moment which the pres--. sure bar is designed to posses.

A still further object of this invention resides in the unique manner in which the lockup bar is designed, which insures that it may be swiftly, easily and economically constructed, assembled, and maintained, and which requires actually fewer part-s than previous less reliable devrces.

These and other objects of the invention, together with additional advantages resulting from its usage, will become increasingly apparent following a consideration of the following specification and its appended claims, when taken in conjunction with the accompanying drawings setting forth an illustrative preferred embodiment of the invention.

In the drawings:

FIG. 1 is a perspective view of an illustrative printing press bed, showing the inventive lockup bar in a typical environment;

FIG. 2 is a plan view of the lockup bar assembly, showing in phantom the manner of its actuation;

FIG. 3 is an enlarged prespective view of the lockup bar assembly of FIG. 2, which more clearly shows certain aspects of same; and

FIG. 4 is an enlarged exploded view of the actuating mechanism of the bar.

The lockup bar assembly of this invention first provides a housing member which is adapted to lie flat upon the bed of a printing press. The housing member is somewhat in the form of an open channel, having an elongate chamber formed in one of its side surfaces. A manually operable cam mechanism is journaled in one end of the housing, and is arranged to exert a longitudinal force upon an elongate pressure bar which is positioned within the chamber formed in the housing. The longitudinallydirected force exerted by the cam upon the pressure bar first forces it sideways in the chamber and through an aperture in the end of the housing, against the side of press bed. As the pressure bar is forced with increasing cam pressure against the side of the bed, the opposite end of the housing moves into contact with the other side of the bed, and the lockup bar becomes locked firmly into place across the bed. The force exerted by .the cam continues to increase, thereby ever increasingly locking the assembly into the bed. When a predetermined amount of force is exerted against the pressure bar to force it against the sides of the press bed, the :bar suddenly begins to bend, and is elastically deformed into a somewhat bowed shape. The central portion of the bow moves outward through the open chamber formed in the housing, and begins to exert a strong force against the printing form, thereby firmly holding the same into position and preventing any possibility of its movement during printing.

Referring now in more detail to the drawings, in FIG. 1 the inventive lockup bar is depicted in the manner in which it lock-s a form of type 12 firmly into position upon the bed 14 of an illustrative printing press 16.

In FIG. 2, the lockup bar 10 is seen to include basically a housing 18, which is preferably a generally rectangular bar having squared end portions, at least one of which (shown at the left in the figure) is formed so as to provide a surface for frictionally engagingone side of the press bed. The lockup bar assembly 10 further includes a cam means 20 which is journalled in the housing near one of its ends, and a suitable handle 22 by which cam means 20 may be manually actuated.

The side of the housing 18 opposite from handle 22 has formed in it a recessed, generally open elongate chamber 24 (shown in FIG. 3). A substantially linear pressure bar 26 (FIGS. 2 and 3) lies within the chamber 24. The chamber is preferably of a depth such that the pressure bar 26 protrudes therefrom by a slight amount even when fully inserted into the chamber with its rear surface engaging the .rear surface of the chamber.

The pressure bar 26 is an elongate and substantially rigid member. As may be seen in FIG. 2, the end portions of the pressure bar are bevelled or cut at an angle, so that the rear face 28 of the bar is somewhat longer than the printing frame-engaging front face 30 thereof. A pair of suitable dowel pins 32 are inserted through housing 18 and pass through chamber 24 at a point aligned with the bevelled portion of pressure bar 26 so that the pins 32 will retain the bar 26 within chamber 28 in the event that the lockup bar 10 is held in an inverted position.

As shown by hidden lines in FIG. 2, and as fully shown in FIG. 4, a suitable cam follower 34 is carriedwithin housing member 18 in a passageway (not shown) formed therein for that purpose adjacent the cam. The cam follower 34 engages cam means 20 at its one end and engages pressure bar 26 at its other end. Also, a suitable plunger 36 is carried within another passageway formed in the other end of housing 18, and this member engages pressure bar 26 at its end opposite cam follower 34. The outer end of plunger 36 is bored and tapped, so that a cap screw or other similar threaded member 38 may be engaged with the plunger 36, thereby providing a length adjustment for the plunger. Since plunger 36 travels Within its passageway longitudinally relative to housing 18, it is desirable that some means be incorporated into the plunger to prevent it from inadvertently falling from the housing 18. One such means is the retaining screw 40, which is threaded into plunger 36 through a suitable aperture 42 formed in housing 18 from its top surface to the plunger passageway. The screw 40 protrudes a brief distance above plunger 36 and remains within aperture 42. In this manner, the allowable travel in any direction for plunger 36 will of course be the diameter of aperture 42, since its sides engage the protruding screw and prevent any further motion of it. As shown in FIG. 4, cam means 20 is basically a drum shaped apparatus having a pair of circular disk-shaped upper and lower guiding or bushing surfaces 44 and 46, respectively. Between these bushing surfaces the cam means 20 has an eccentric, generally eliptical cam surface 48, with which cam follower 34 is mated.

In operation, the novel lockup bar assembly disclosed herein is controlled by a single movement of the handle 22. As indicated by the phantom lines in FIG. 2, and as within their journals in housing 18. This causes cam surface 48 to move in an eccentric path relative to the bushing surfaces, however, and to exert a force against cam follower 34 which causes it to move longitudinally relative to housing 18, toward the side of the press bed.:

The movement of cam follower 34 is transmitted to pressure bar 26, and from it to plunger 36 and its adjusting screw member 38, until the latter encounters the side of the bed. As soon as this occurs, the movement of these members is transmitted to the housing 18 itself,

and it is moved in the opposite direction, into contact with the other side of the bed.

As the handle 22 continues to move, cam means 20 continues to exert a force against its follower 34 and, in turn, against pressure bar 26, plunger 36, and screw 38. This causes the locking bar 10 to be firmly secured in place across the bed of the press, within ever-increasing force. Still handle 22 continues to move, and when pressure bar 26 has been placed under a predetermined amount of stress, it begins to bend or how in elastic deformation. The forward face 30 of the pressure bar thus begins to contact the form of type 12 with an initial degree of force. The final movement of the handle 22 and cam means 20 increases the force which holds lockup :bar 10 in place across the bed of the press, while at the same time it applies an increasing force directly to the printing form which is essentially normal to the lockup bar and parallel to the sides of the bed, thereby firmly securing the form t in position upon the bed.

Thus, it will be quite apparent that the use of the novel lockup bar 10 is very simple indeed. All the operator need do is to place the printing form 12 into position upon the bed 14 of the press, place the lockup bar 12 immediately behind the form and in firm contact there-. r with, and then move the handle 22 from its first to its second or actuated position, thereby accomplishing all of the foregoing movements and forces in one simple motion.

Should it be desired to use the lockup bar 10 upon another press having somewhat different dimensions, the

effective length of the lockup bar may easily and quickly be altered by turning the adjusting screw 38 in one or the other direction relative to plunger 36. During any such adjustment, it is to be noted that plunger 36 will rotate a very brief distance, and then set screw 40 will encounter one of the sides of aperture 42, thereby preventing the plunger from any further rotation and facilitating the adjustment of screw 38.

It should also be noted that a very slight adjustment of screw 38 will serve to change the amount of pressure which complete actuation of the cam means causes to be exerted against the sides of the press bed and against the printing form. Thus, it will be seen that the bending moment which the pressure bar 26 is designed to exhibit effectively determines the difference between the force which will be exerted against the sides of the bed and the force which will be exerted against the printing form, while adjustment of screw 38 effects a simultaneous change in both of these force components.

In connection with the operation of the novel lockup bar assembly, it should be expressly pointed out that (as illustrated in FIG. 2) the shape of the pressure bar 26 and the depth of the chamber 24 within which it lies are such that theextreme ends of the pressure bar, which engage cam follower 34 and plunger 36, have considerably Iljess area than the complete cross-section of the pressure ar. the flat portion of the bar, and not against its bevelled or angled portions leading to forward edge 30. In this manner, the compressive force exerted between follower 34 and plunger 36 is not uniformly applied across the ends of the pressure bar. On the contrary, this force is applied across only a minor portion of that width. Conse- That is, the follower and plunger act aaginst only i quently, as the force increases and the pressure bar begins to be elastically deformed, the portion of the pressure bar between the follower and plunger, i.e., along its rear surface 28, is actually shortened, whereas the remainder of the bar, including forward face 30, is not shortened. This feature produces the bending moment of the pressure bar, and its resultant bowing out against the printing form. If this arrangement were not made, the pressure bar, and probably the housing chamber 24 as well, would have to be formed with a slight permanent curvature, or else other suitable measures would have to be taken, so that the pressure bar would bow outward in the correct direction each time. Otherwise, the direction in which the pressure bar would bow would be unpredictable, and it might bow inward against the rear of the chamber and merely block the bar from further actuation.

Having now completely described the structure which illustrates a preferred embodiment of my unique lockup bar assembly and also the manner in'which the same is operated, certain variations in structural detail and certain modifications of the preferred embodiment may occur to those who have studied this specification which do not depart from the spirit of the invention, nor from the inventive concept which underlies it. Accordingly, all such modifications and alterations are to be considered as a part of this invention, unless they are expressely excluded by the terms of the claims appended here below.

I claim:

1. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed; elon gated force-transmitting means movably carried by said housing for contacting one side of said press bed and forcing one end of said housing against the other side of the bed; and means associated with said housing and said force-transmitting means for exerting a force against portions of the latter, including portions located rearwardly of the longitudinal axi thereof, such that said forcetransmitting means is first placed in compression between said housing and said one press bed side and then resiliently bowed away from said housing and against said printing form as a result of said force on said rearwardlylocated portions and upon the exertion of a predetermined amount of such force after said housing has been forced against said other side of said bed, whereby said housing is locked across said bed between its sides and said form is urged away from said housing and firmly secured upon said bed.

2. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed; means carried by said housing and arranged to be relatively movable for contacting the opposite sides of said bed upon such movement; elongate force-transmitting means associated with said housing and located between said contacting means, for forcing the latter into contact with said sides of said press bed; and means associated with said housing and said force-transmitting means for exerting a force against portions of the latter, including portions thereof located rearwardly of the longitudinal axis thereof; said force-transmitting means having a bending moment such that when an initial amount of such force is first applied thereto said contacting means are forced against the opposite sides of said press bed with a predetermined pressure, and when such force is increased said transmitting means are bowed laterally of said housing and toward said printing form as a result of the force on said rearwardly-located portions, said force-transmitting means when bowed applying a force against said form which is essentially parallel to the sides of said bed and normal to said housing.

3. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed, said housing having a surface associated therewith for contacting one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; force-transmitting means carried by said housing and arranged to act upon said housing and said contacting means to force said contacting means and contacting surface into compressive contact against the opposite sides of said press bed, thereby locking said housing into position thereupon; and means associated with said housing and said force-transmitting means for exerting a force against portions of the latter, including portions thereof located rearwardly of the longitudinal axis thereof; said force-transmitting means having a bending moment such that when an initial amount of such force is first applied thereto said housing contact surface and said contacting means are forced against opposite sides of said press bed with a predetermined pressure, and when such force is increased said transmitting means are bowed laterally of said housing and against said printing form as a result of the force on said rearwardly-located portions, said forcetransmtiting means when bowed applying a force against said form which is essentially parallel to the sides of said bed and normal to said housing.

4. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing having a generally flat bottom portion adapted to lie upon said press bed, said housing having an end surface for contacting one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifiiy resilient member carried by said housing and extending between said housing and said contacting means; and means operably coupled to said member for exerting a force upon portions thereof including portions located rearwardly of the longitudinal axis thereof, such that said member forces said contacting means and housing end surface into compressive contact against the opposite sides of said press bed, thereby locking said housing into position thereupon; said member having a bending moment such that after said housing is securely locked between said sides of said bed in the aforesaid manner the exertion of force on said rearwardly-located portions of said member causes said member to be resiliently bowed laterally of said housing and against said printing form, thereby applying a force against the form which is essentially parallel to the sides of said bed and normal to said housing.

5. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing having a generally flat bottom portion adapted to lie upon said press bed, said housing further having an elongate chamber formed along the forward side thereof and a surface on one of its ends adapted to contact one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifily resilient member lying within said housing chamber and extending between said housing and said contacting means; and means operably coupled to said member for exerting a force upon portions of the member located rearwardly of the longitudinal axis thereof, such that said member forces said contacting means and housing end surface into compressive contact against the opposite sides of said press bed, thereby locking said housing into position thereupon; said member having a bending moment such that after said housing is securely locked between said sides of said bed in the aforesaid manner the exertion of force on said rearWardly-located portions of said member causes said member to be resiliently bowed laterally of said housing and against from said chamber toward said printing form, thereby applying a force against the form which is essentially parallel to the sides of said bed and normal to said housing.

6. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing having a portion adapted to lie upon said press bed, said housing further having a surface associated therewith for contacting one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifiiy resilient member carried by said housing and extending between said housing and said contacting means; a manually operable cam means supported by said housing, for exerting a generally come pressive force upon said member such that the member forces said contacting means and said contacting surface of said housing into compressive contact against opposite sides of said press bed, thereby locking said housing into position thereupon; said cam means and said resilient member arranged such that said force is applied to portions of the member located rearwardly of the longitudinal axis thereof and said member having a bending moment such that when said housing is securely locked between said sides of said bed the exertion of said force on said rearwardly-located portions causes said member to be bowed laterally of said housing and against said printing form, thereby applying a force against the form which is essentially parallel to the sides of said bed and normal to said housing.

7. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing having a portion adapted to lie upon said press bed, said housing having an elongate chamber formed along the forward side thereof and a surface on one of its ends adapted to contact one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifiiy resilient member lying Within said housing chamber and extending between said housing and said contacting means; a manually operable cam means supported by said housing for exerting a generally compressive force upon said member such that the member forces said contacting means and said contacting surface of said housing into compressive contact against opposite sides of said press bed, thereby locking said housing into position thereupon; said cam means and said resilient member arranged such that said force is applied to portions of the member located rearwardly of the longitudinal axis thereof and said member having a bending moment such that when said housing is securely locked between said sides of said bed the exertion of said force on said rearwa'rdly-located portions causes said member to be bowed laterally of said housing and outwardly from said chamber against said printing form, thereby applying a force against the form which is essentially parallel to the sides of said bed and normal to said housing.

8. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed; said housing having relatively movable means for contacting the opposite sides of said bed; force-transmitting means operably coupled between said relatively movable contacting means for forcing the same into contact with the opposite sides of said press bed; and means mounted upon said housing for exerting a compressive force against those portions of said force-transmitting mean-s located rearwardly of the longitudinal axis thereof; said force-transmitting means having a bending moment in response to the application of such force such that when it is under a predetermined such compressive load it will be bowed laterally of the direction of said load; and means for directing such bowing of said force-transmitting means toward said printing form, whereby a force is applied against said form which is essentially parallel to the sides of said bed and normal to said housing.

9. A lockup bar assembly for looking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed, said housing having a surface for contacting one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifiiy resilient member carried by said housing and extending to ward and in contact with said contacting means; and

means for exerting a force between said housing and said member such that the latter force-s said contacting means and contacting surface into compressive contact against opposite sides of said press bed, thereby locking said housing into position thereupon; said cam means acting upon saidmember such that said force is applied thereto at areas occurring rearwardly of the longitudinal axis of the member; said member having a bending moment in response to the application of such force such that when it is under a predetermined such compressive load it will be bowed laterally 0f the direction of said load; and means for directing the bowing of said member toward said printing form when under such a load, whereby a fence is applied against the printing form which is essentially parallel to the sides of said bed and normal to said housing.

10. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed, said housing having an elongate chamber formed along one side thereof and a surface on one of its ends adapted to contact one side of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifily resilient member lying within said housing chamber and carried by said housing and extending toward and in contact with said contacting means;

and means for exerting a force between said housing and i said member such that the latter forces said contacting means and contacting surface into compressive contact against opposite sides of said press bed, thereby locking said housing into position thereupon; said cam means acting upon said member such that said force is applied thereto at areas occurring rearwardly of the longitudinal axis of the member; said member having a bending moment in response to the application of such force such that when it is under a predetermined such compressive load it will be bowed laterally of the direction of said load; and means for directing the bowing of said member laterally of said housing and outwardly from said chamber toward said printing form, whereby a force is applied against the printing form which is essentially parallel to the sides of said bed and normal to said housing.

11. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: a housing portion adapted to lie upon said press bed, said housing having an elongate chamber formed along one sidethereof and a surface on one of its ends adapted to contact one side. of said press bed; means movably carried by said housing for contacting the other side of said press bed; a stifliy resilient member lying within said it is under a predetermined such compressive load it will be bowed laterally of the direction of said load; and means for directing the bowing of said member laterally of said housing and outwardly from said chamber toward said printing form, whereby a force is applied against the printing form which is essentially parallel to the sides of said bed and normal to said housing.

12. A lockup bar assembly for locking a printing form into position upon the bed of a printing press, comprising: an elongate housing having a generally flat bottom adapted to lie upon said press bed and having an end surface for abutting contact with one side of said bed; said housing defining reces d Chamber formed inwardly of the housing from the forward side thereof and extending long a major portion of said side; an elongate stiflly resilient bar means located within said chamber and at least slightly slidable therewithin; said bar means including a plunger member slidably retained within the end of said housing opposite that having the aforesaid end surface and extendable from such opposite housing end; a force-generating cam means mounted for camming movements upon said housing and arranged to exert a generally compressive force against the end of said bar means opposite said plunger member, such that said bar means forces its plunger member outwardly from said housing against one side of said press bed and reactively forces said housing in an opposite direction to bring its said end surface against the other side of said bed, thereby locking said housing into position thereupon; said cam means and bar means having areas of contact located rearwardly of the longitudinal axis of the bar means; and said bar means having a bending moment such that when said housing is securely locked between the sides of said bed the application of said force on said rearwardly-located bar means areas causes said bar means to be bowed laterally of said housing and at least partially out of said chamber, against said printing form, thereby applying a force against the latter which is essentially parallel to the sides of said bed and normal to said housing.

13. The lockup bar assembly defined in claim 12, wherein said cam means includes a rotary cam member journaled in said housing and a cam follower member for contact with the said rearwardly-located areas on the said end of said bar means.

14. The lockup bar assembly defined in claim 13, wherein said bar means includes a mutually separable stiflly resilient rod element and plunger member; wherein said plunger member is slidably seated in an aperture which extends through said end of said housing and into said elongate chamber; and wherein said chamber has a rearward wall located to position that end of said rod element which is adjacent said plunger member such that only the areas on said end which are rearward of the longitudinal axis of the rod element are in contact with said plunger member.

15. The lockup bar assembly defined in claim 14, wherein the ends of said rod element are angularly chamferred or bevelled from the forward edge of the rod outwardly to the ends thereof and at least to the longitudinal axis of the rod, such that the areas at the end extremities of the rod are limited to those which are located rearwardly of said axis.

References Cited by the Examiner UNITED STATES PATENTS 462,799 11/ 1891 Isaacs 101-390 X 682,466 9/1901 Hardy et al 27642 730,526 6/1903 Friese 27643 1,292,701 l/19l9 Buvinger 10l-39l 2,823,608 2/ 1958 Vandercook et al. 101-390 ROBERT E. PULFREY, Primary Examiner.

J. R. FISHER, Assistant Examiner. 

11. A LOCKUP BAR ASSEMBLY FOR LOCKING A PRINTING FORM INTO POSITION UPON THE BED OF A PRINGING PRESS, COMPRISING: A HOUSING PORTION ADAPTED TO LIE UPON SAID PRESS BED, SAID HOUSING HAVING AN ELONGATE CHAMBER FORMED ALONG ONE SIDE THEREOF AND A SURFACE ON ONE OF ITS ENDS ADAPTED TO CONTACT ONE SIDE OF SAID PRESS BED; MEANS MOVABLY CARRIED BY SAID HOUSING FOR CONTACTING THE OTHER SIDE OF SAID PRESS BED; A STIFFLY RESILIENT MEMBER LYING WITHIN SAID HOUSING CHAMBER AND EXTENDING TOWARD AND IN CONTACT WITH SAID CONTACTING MEANS; A MUTUALLY OPERABLE CAM MEANS FOR EXERTING A FORCE BETWEEN SAID HOUSING AND SAID MEMBER SUCH THAT THE LATTER FORCES SAID CONTACTING MEANS AND CONTACTING SURFACE INTO COMPRESSIVE CONTACT AGAINST OPPOSITE SIDES OF SAID PRESS BED, THEREBY LOCKING SAID HOUSING INTO POSITION THEREUPON; SAID CAM MEANS ACTING UPON SAID MEMBER SUCH THAT SAID FORCE IS APPLIED THERETO AT AREAS OCCURING REARWARDLY OF THE LONGITUDINAL AXIS OF THE MEMBER; SAID MEMBER HAVING A BENDING MOMENT IN RESPONSE TO THE APPLICATION OF SUCH FORCE SUCH THAT WHEN IT IS UNDER A PREDETERMINED SUCH COMPRESSIVE LOAD IT WILL BE BOWED LATERALLY OF THE DIRECTION OF SAID LOAD; AND MEANS DIRECTING THE BOWING OF SAID MEMBER LATERALLY OF SAID HOUSING AND OUTWARDLY FROM SAID CHAMBER TOWARD SAID PRINTING FORM, WHAERBY A FORCE IS APPLIED AGAINST THE PRINTING FORM WHICH IS ESSENTIALLY PARALLEL TO THE SIDES OF SAID BED AND NORMALLY TO SAID HOUSING. 